Manufacture of sheet glass



Dec. 29, 1931.

R. GENENGER MANUFACTURE OF SHEET GLASS Filed March 27, 1930 3Sheets-Sheet 1 Dec. 29, 1931.

R. GENENGER MANUFACTURE OF SHEET GLASS Filed March 2'7, 1930 3Sheets-Sheet 2 Dec. 29, 1931.

'R. GENENGER MANUFACTURE OF SHEET GLASS Filed March 27, 1950 3Sheets-Sheet 3 each 5 millimeters thick.

Patented Dec. 29, 193i RICHARD GENENGER 0F AACHEN-FORST, GERMAiNY,ASSIGNOR, BY MESNE ASSIGN- MENTS, TO THE AMERICAN BICHEROUX COMPANY, ACORPORATION OF DELAWARE MANUFACTURE or snnnr, eLAss Application filedMarch 27, 1980, Serial No. 439,482, and in Germany November 28, 1929.

This invention relates to the manufacture of sheet glass on rollingmachines with a pair ofcooperating forming rolls, and it has for its mamobject to so improve the known rolling process that it is possible tomake glass sheets of different thickness from one and the same charge ofliquid glass mass, this being attained by changing during the rollingoperation and without interrupting'the samethe distance between theforming rolls so that the ribbon formed has successive sections ofvarying thickness, which by a subsequent division at the joints betweenthem yield sheets of correspondingly different thicknesses.

This improved process possesses the following advantages. Glass-worksusing this process can accommodate their production much better to theorders placed with them than hitherto. .When the glass ribbons or sheetsare produced intermittently from the contents of one or more meltingpots, the process allows of a better utilization of the pots. The chargeof a-melting pot of ordinary size generally yields two sheets with athickness of 9,1nillimeters, a length of about 6,5 meters and a width ofabout 3,5 meters, while the remainder of the charge is .not sullieientto make a third sheet of the same dimensions. Therefore, the third sheetif formed will have a considerably smaller length or the remainder ofglass is left unused in the machine. A much better utilization is,however, obtained when rolling from the charge contained in a pot sheetsof the said length and width but of different thicknesses, for instanceone sheet 8 millimeters thick, at second sheet (3,5 millimeters thickand a third sheet 4,5 millimeters thick, or one sheet 9 millimetersthick and two sheets The use of the present process is of particularadvantage in works where the glass sheets made from each charge, forinstance from the contents of each pot, are delivered by means oftravelling transporting tables to a plurality of lccrs which correspondin number to the number of sheets formed from each charge and which arearranged side by side laterally of the track of the transporting tables.

When in such a plant three sheets are formed from the contents of a potby cutting the glass ribbon at the gaps between successive tables, thefirst sheet is carried to the leer which is most remote from the rollingmachine, the second sheet is carried to the leer next but one to themachine and the third sheet is carried to the leer located nearest therolling machine. However, in proceeding with the delivering of theseveral sheets in this manner, it may become diflicult to get the sheetcut off first and eventually the second sheet too stowed in asufficiently hot condition because of the great distances between themachine and the respective leers, especially if the sheets are of asmall thickness, say 4 to'6,5 millimeters. This difliculty may result inthe formation of cracks and a bad evenness. The third sheet is notsubjcctedto this danger, because it does not take much time to transportthis sheet through the small distance from the rolling machine to thenearest leer. The diiliculty mentioned becomes the greater, the moresheets are made from eachcharge and the more leers must accordingly beprovided, that isto say the longer the distance becomes over which thefirst sheets have to travel to reach their lcers. The difficulty can beovercome according to the invention by making the first sheet of greatthickness, say 9 millimeters. the second sheet of a smaller" thicknessand the third sheet of a still smaller thickness, or by making thev twofirst sheets comparatively thick, for example 9 millimeters, and thethird sheet very thin, for example 4 millimeters. In this case, onlysheets of great thickness-aboutfl millimcters-have to be carried over acomparatively great distance, and such sheets can stand the rolongedinfluence of the outer being injured.

The process can he carried out at low costs with any existing multi-iollglass rolling machine.

When applied to a glass rolling plant in which the glass ribbon is takenoil the machine by travelling transporting-tables and severed intosheets by cutting the ribbon at the gaps between successive tables, thetimes atmosp ere without,

at which the distance between the forming rolls is altered, is chosen sothat the wedgeshaped portions formedbetween the sheets or ribbonsections of diflerentthickness in passing onto the tables will overliethe gaps between the tables. As the ribbon is cut at these gaps the lossof glass is only inconsiderable.

In the drawings:

Fig. 1 is a perspective view of a glass rolling machine with one form ofa device for adjusting the distance between the forming rolls Fig. 2 isa side View, partly in section, of one'of the roll stands with theadjusting device Fig. 3 is a view similar to Fig. 1 of a machine withanother form of adjusting device,

Fig. 4 is a side view of one of the roll stands of this machine, and

Figs. 5 and 6 are diagrammatic side elevations of a sheet glass rollingplant illustrating the formation of sheets of different thickness.

It is assumed that the machines illustrated in Figs. 1 to 4, first forma thick sheet P and in succession thereto a thin sheet P. 1 designatesthe roll stands, 2 are the upper and 3 the lower forming rolls, 4 thetravelling transporting tables and 5 the chutes over which the glassribbon glides from the machine to the transporting tables. The bearings6 of the upper forming roll 2 are vertically adjustable in the stands 1.

According to Figs. 1 and 2, the bearings 6 are suspended by means ofbolts 7 on supporting members mounted in the stands 1. Interposedbetween the bearings 6 and the members 8 are compression springs 9 whichtend to force the bearings 6 downwardly. The supporting members 8 arefastened to the lower ends of screw spindles 10, which are in engagementwith and guided in central threaded bores of worm wheels 12 mounted onor in the top pieces of the stands 1. The wheels 12 mesh with worms 13which are fastened on a common shaft 14. It will be understood that byrotating the shaft 14 in one direction or the other the bearings 6 ofthe upper forming roll 2 are raised or lowered, whereby the distancebetween the form ing rolls 2 and 3 and the thickness of the glass ribbonformed between them are altered. The shaft 14 is preferably operatedfrom a motor 15 which is kept running constantly. Interposed between themotor 15 and the shaft 14 is an electromagnetic clutch 16 which iscontrolled by an electric circuit 17. The closing of this circuit iseffected through the intermediary of a switch 18, which is located onone side of the track of the tables 4 and adapted to be automaticallyactuated by a lug 19 carried by each of the tables. Fastened on one ofthe worm wheels 12 so as to rotate in unison therewith is a disc 20which carries an adjustable tripping member 21, which is adapted to actat the proper times on a cut-out 22 for interrupting the circuit 17 andrendering the clutch 16 inoperative.

At the beginning of the rolling operation the distance between the rolls2 and 3 is set in accordance with the desired thickness of the firstsheet P, i. e. the first section of the glass ribbon. The motor 15 isrunning and the clutch 16 is kept inoperative. As soon as the lug 19 ofthe first table 4 with the glass ribbon thereon reaches the switch 18,it actuates the latter so that it closes the circuit 17, throwing in theclutch 16. Thereby motion is imparted to the shaft 14, worms 13 and wormwheels 12 until the tripping member 21 of the disc 20 actuates thecut-out 22. Through the said motion the screw spindles 10 and thebearings 6 are lowered so that the distance between the forming rolls 2and 3 is reduced. The position of the tripping member 21 and the pitchof the screw spindles 10 are so chosen that the lowering of the upperforming roll 2 corresponds to the difference of thickness between thesheets or sections P and P. As the motor 15 is running constantly, thelowering of the roll 2 will take place instantaneously, thus avoidingany delay which would otherwise be caused by the starting of the motor.The switch 18 and the lugs 19 are located. in such positions that bytheir co-oepration the wedge-shaped connecting portion 2 between thesections P and P in passing onto the tables 4 will overlie the cuttinggap 4 between the tables 4. As the downward displacement of the upperroll 2 takes place very quickly the portion 2 becomes very short, and asthis portion is deposited over the cutting gap and a transverse strip ofglass is, per se, generally cut out of the ribbon at these gaps fordividing the ribbon into the desired units or sheets, the loss entailedthrough the wedge-shaped portions 1) is only extremely small.

In the form according to Figs. 3 and 4, the journals of the upper roll 2are eccentrically mounted in bushes 23 which at the same time form wormwheels 23. These wheels are engaged by worms 24 fastened on shafts 25which are adapted to be rotated by bevel gears 26 from the common shaft14. The operation of this device is similar to that of the deviceillustrated in Figs. 1 and 2. The only difi erence consists in that theraising and lowering of the upper roll 2 is brought about by the turningof the bushes 23 and that the tripping member 21 for the cut-out 22 isadjustably fixed to one of the bushes 23. The bearings 6 of the upperroll 2 are forced downwardly by compression springs 9 interposed betweenthe bearings and the top pieces 11 of the stands 1.

The disc 20 and the bush 23 which carry the tripping member 21, arepreferably provided with a scale for the various thicknesses of theglass sheets to be formed. They are further provided with suitablydistributed holes or cavities,'in one or the other of which the trippingmember is fastened according to the thickness to be given to the sheets.But there may also be used any other suitable means for clamping thetripping members in, the desired positions.

While I have described two forms of devices for changing the distancebetween the two forming rolls, it will be understood that there exists avariety of other possibilities for effecting this adjustment.

Figs. 5 and 6 show the rollin of sheets of various thicknesses. at twodi erent stages. The rolling process illustrated in these twofiguresdiflers from that described with relation to Figs. 1-4 ins thatthere arefirst formed the thinner sheets or ribbon sections and then thethicker ones. Therefore, in the course of the operation the upperforming roll is not lowered but raised. a

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent, is 1 1. The process of making sheet glasswhich consists in delivering a charge of molten glass to a pair ofcooperating forming rolls, passing the glass through the pass betweenthe rolls to form a ribbon, feeding this ribbon onto a series oftravelling trans orting tables coupled end by endto each 0t er andhaving transverse gaps between their ends,

'changing the distance between the forming rolls during the rollingoperation to give 7 various thicknesses to successive sections of theribbons, eifecting the change of the roll distance at such intervals asto cause the joints between the several ribbon sections to take theirposition on the transporting tables above the, said gaps, and dividingthe ribbon In testimony whereof I have signed my name to this secification.

ICHARD GENENGER.

into individual sheets by cuttin it trans versely at the gaps betweenthe ta les.

2. In an apparatus for making sheet glass, in combination a pair ofcooperating forming rolls, stands for these rolls, bearings the standsfor the journals of the rolls, means for adjusting the bearings of oneroll relatively to the other for between the rolls, travelling.transporting tables for receiving the glass ribbon emerging from betweenthe forming rolls, a motor for operating the roll adjusting means, aclutch interposed between the motor and the roll adjusting means, anelectric circuit for controlling this clutch, ,a switch arranged tochanging the distance a be actuated by the transporting'tables for qclosing the circuit and rendering the said clutch operative, and anotherswitch adapted to be operated by the roll adjusting means for openingthe circuit-and rendering the clutch inoperative.

3. In an apparatus for making sheet glass, the combination with a pairof cooperating

